1. Field of the Invention
The present invention relates to a driver and a display device including the driver.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) includes a pair of display panels including pixel electrodes, a common electrode, and a liquid crystal layer with dielectric anisotropy interposed between the panels. The pixel electrodes are arranged in the form of a matrix, and are connected to switching elements such as thin film transistors (TFTs) to sequentially receive data signals per pixel row. The common electrode that receives a common voltage extends over substantially the entire surface of one of the panels. From a circuit perspective, the pixel and common electrodes and the liquid crystal layer disposed therebetween form a liquid crystal capacitor. The liquid crystal capacitor together with a switching element connected thereto form a basic unit for a pixel.
Voltages to the two panels generate electrical fields in the liquid crystal layer that vary the transmittance of light passing through the liquid crystal layer, thereby displaying desired images. In order to prevent the liquid crystal layer from deteriorating due to extended application of a unidirectional electrical field, the voltage polarity of the data signal with respect to the common voltage is periodically inverted, e.g., per frame, per pixel row, or per pixel.
The LCD includes a gate driver for transmitting a gate signal to a gate line for turning on/off the switching element of a pixel. The LCD also includes a gray voltage generator for generating a plurality of gray voltages, a data driver for selecting a voltage corresponding to image data among the gray voltages, and a signal controller.
The gate driver is formed in the same manufacturing process as the switching element and is integrated with the display panel. The pixels are disposed in a horizontal direction to increase the number of gate lines by three times and decrease the number of data lines to be ⅓, the cost may be reduced while realizing the same resolution. In addition, according to the increased number of the gate lines, the gate driver may be provided at the right and left sides of the display panel to permit alternately application of the gate signal.
However, the pixel charging rates may differ between a side that is adjacent to the gate driver and a side that is far from the gate driver because of a resistor-capacitor (RC) delay. Thus, pixel voltages applied to the pixel may differ, and neighboring pixels may have different brightnesses even when the data voltage indicating the same brightness is input.
Since it is required to alternately apply the gate signals from the two gate drivers positioned at right and left sides of the display panel, it is difficult to simultaneously apply the gate signals, particularly for a small and medium sized display device.